Light weight, functional and stable The Android default email app is v boring n dull. I use K-9 for my two Outlook, one Yahoo and one own domain accounts. My two Gmail accounts are handled by default Gmail app. Though I thought it was slow in push notifications, but that seems to be working ok now. Everything I want from an email app works flawlessly in K-9. It's lightweight and superior in overall performance. Thumbs up!
Edit May 18th 2016: Has started reporting wrong sender in emails. Headers are correct, but every email is being reported as coming from a single sender. Minus 1 star... Previous review : Much better than the stock email client. A big plus is allowing multi-select and unified account view options
Rapid sync, no clutter, privacy Thanks to the developers for this wonderful application which replaces my android stock app. I almost gave up on finding a mail app which doesn't ask for a ton of permissions until I found K9. A few minor suggestions for improvements: It should be possible to move mails to folders of different accounts, and generally the moving of mails could still be simplified. Another desirable feature would be a rapid delete gesture and an undo button for the last move/delete action.
Much better than factory mail client I love that you can store messages on the SD card as I was running out of memory on the device storage. I have Exchange sync perfectly an IMAP account and also Gmail and everything works perfectly. For people having issues with Exchange Google which URL you are supposed to use.
User folder and please Please please please please allow at least one user folder, eg "Pending" (pop3) - then you'll get your otherwise richly deserved 5th star. Sometimes deleted emails arise from the dead again. But apart from that, it's a great app!
4 years of happy mobile mail :) This is an outstanding email app! It works perfectly, super customizable! Also has a very unique and comfortable interface. It's that simple to describe it, nothing else to say, really, because it's just great! Last year, when I bought a new phone, i didn't even try its own mail client app because i got used to k9 a lot. Thanks for your great app and amazing support!
Changes in v5.010:
• Fixed packaging error; v5.009 was missing translations in some cases
Changes in v5.009:
• Protect against the Surreptitious Sharing vulnerability
• Improved MIME type handling when other apps share files to K-9 Mail